https://en.wikipedia.org/wiki/Oyster_(company)

There was already one that existed in the web 2.0 era. Founded in 2012, raised a $3M seed from Founders Fund and a $14M A. Completely failed though and was acquihired by Google to have the founders lead Google Play Books.

Amazon now has Kindle Unlimited but I think it's mostly romance slop and self-published books. Seems like publishing rightsholders were just too inflexible to let the business model take off.

Yeah I like reading somewhat obscure history books- no public library carries those and they're extremely expensive if you can find them.

Usually funded by universities and foundations anyway because there's no real commercial market.